Machine for recessing plaster lath board



Get. 14 1924- E. WESTBERG ET AL MACHINE FOR RECESSING PLASTER LATH BOARD Octs 14 'i924- E. WESTBERG ET AL MACHINE FOR RECESSING PLASTER LATH BOARD 1923 3 Sheets-Sheet 2 Ffiled Jant 2 l@ nan aan n n n u w E a n Oct. 14 i924. ,51l,486

E. WESTB'ERG ET'AL.

MACHINE FOR RECESSINGl PLASTER LATH oARn JNVENToR y Patented Oct. 14, 1924.

UNITED STATES EDWARD WESTBERG AND JOSEPH STRAND, OF LOS ANGELES, CALIFORNIA.

MACHINE FORA 'REGESSING BLASTER LATI-I BOARD.

Application Vfiled January 2, 1923.

To all whom t may concern:

Be it known that We, EDWARD VnsrnnRG and .Josera-i STRAND, citizens ofthe United States, vresiding at Los Angeles, county of Los Angeles, and State of California, have invented new and useful Improvements in Machines for Recessing Plaster Lath Board, ofl which the following is a specification.

I:this invention relates to machines employed in the manufacture of plaster lath board, and particularly pertains to a inachi-ne forforming obtrusions in the surface of sheets of lath board of the character described in our co-,pending application entitled Plaster lath board and .method 'of making the same, Serial No. 602,298, filed Nov. 20, 1922.

It is the principal object of the present invention to provide a simple, efficient and automatically operating machine Which may be employed to inexpensively and expedi tiously form depress-ions in Aand to be systematicallyarranged over the surface of sheets of plaster lath board.

The invention contemplates the use of gangs of rotary cutters arranged in desired spaced yrelation to keach other, operating in conjunction With an automatically operating mechanism .adapted to deliver sheets of plaster lathboard thereto `and to feed the boards yagainst the cutters to form a plurality of depressions of desired size and depth in the surface of the board.

One form which the invention may assume is exemplified in the following description and illustrated by Way of example inthe accompanying drawings, in Which:

Fig. 1 is a view in longitudinal section through a machine embodying the invention.

Fig. Q, .is a side elevation of the same.

Fig. 3 is a plan view of the machine.

.Fig. -t -is va transverse section. through the machine taken on line le-4 of Fig. 1.

Fig. 5 is a perspective view of a portion of a sheet of plaster lath board With depressions in the surface thereof such as formed by the machine.

Fig. 6 is a fragmentary view disclosing the table guide member and the lifting cam.

Fig. 7 is a perspective vievv disclosing` a portion of a mandrel with cutters mounted thereon.

Referring moreL particularly to the drawings, 10 indicates a main frame formed with hearings 11 which support a pair of hori- Serial No. 610,130.

zontal end vshafts 12and 12a. These shafts are fitted With sprockets 14, over which chains 15 are led. These chains constitute a conveyor and are yfitted with lugs 16 `arranged in pairs to accommodate sections of plaster lath board .17.

Mounted on the frame, intermediatethe conveyor chains 15 area pair of horizontal guide members 18. 1t is intended that the conveyor should carry sections of plaster board along these guides to predetermined positions over a centrally located verticaily reciprocable table 19. This table is fitted With vertical guides 19a aligned With the guides 1S When the table is disposed in its normal position.

The table is .guided for vertical reciprocable movement by guide yokes 20 Which are fixed to the under side of thetable and slidably engage stationary guide blocks 2O secured at each side of the main frame.

Two sets of rotatable cutters 21 are feathered onto horizontal mandrels 22 .and are disposed above the table. These mandrels are journalled at their ends in a subframe 22a mounted above the.y main frame as shown in Fig. lf. Themandrels of one set are disposed at right angles -With relation to the other set, as it is intendedthat the sets of cutters co-operate to form rows. of relatively staggered depressions in thesu-rface of the board arranged alternately at right angles to each other. 4

The conveyor is intermittently opera-ted to feed plaster boards beneath the sets of cutters. V5.7 hen the boards are properly positioned beneath the cutters the operation of the conveyor is momentarily interrupted and the table 19 is vertically reciprocated to raise the boards into contact With the cutters. To accomplish this, a drive shaft 23 is journalled adjacent the frame and is fitted With a Worm 23a. This'ivorm meshes with a Worm gear 24 fixed en an operating shaft 25. The shaft is provided With a mutilated gear 26 having two sets of teeth 27 Which are formed on diametrically opposed sides of the gear. These sets of teeth are adapted to alternately mesh With `a pinion 28 secured on the shaft 12a of the conveyor and With a pinion 29 iixedon a shaft 30. This shaft is connected by sprockets and chain connections 31 to a pair Vof horizontal cam shafts 32. These shafts are disposed below the table adjacent `the ends thereof andare fitted with cams 33; that is, each i idly lowered during each half revolution of the cam shafts.

It should be stated that the number of teeth in each set 27 on the mutilated drive gear is sufficient vto impart one-half revolution toV each of the pinions 28 and 29. A half revolution of the pinion 28 is sufficient to impart one complete step o-f advance to the conveyor. This step is suiiicient to transfer' a board fed to the machine to a position below the first set of cutters, and to advance a board positioned below the first set of cutters to a position below the second set, etc.

Reference being had to Fig. l, it is seen that the sets of teeth 27 on the mutilated drive gear are so positioned that the pinions 28 and. 29 .arel alternately operated. Therefore, during the rest period of the conveyor the cams will be'actuated to reciprocate the table, and during the idle period of the cams the conveyor will advance the sheets of board one step.

To drive the cutters a bevel gear is fixed on the end of the drive shaft 23 and is in mesh with a gear 36 secured on a stub shaft 37. The stub shaft drives the first cutter set'through a gear connection 38. It also drives the second set by a bevel gear connection 39. The mandrels of each set are connected together byv spur gear trains e() which operate to drive the mandrels in op posite directions. Each mandrel willthen rotate the cutters thereon in a direction opposite that of the cutters on the adjacent mandrels. This is desirable as it eliminates the tendency of the cutters to shift the board out of position when they engage the surface thereof.

As shown in Fig. 7, the cutters yare feathered on the mandrels and are secured in place by set screws 4l. This mounting permits the cutters to be spaced to form slots in the sheets of board at any desired distance apart.

In operation, sheets o-f the plaster lath board are fed to the machine between the guides 18 at the point indicated at A. Assuming that the drive shaft 23 is being continuously driven and that the mechanism has assumed the position shown in Fig. l.

continued rotation of the mutilated gear 26 will impart turning movement to the pinion 29. This pinion, through the medium of the shaft and the sprocket and chain conneotions 31, will rotate the cam shafts 32. As these cam shafts rotate, the cams v33 thereon will slowly raise the table 16 and force the sheet of bo-ard thereon into conf tact with the cutting edge of the continuously rotating cutters.` The boards will be raised by the table until depressions have been cut to a suitable depth therein. The table will then be quickly flowered. As described, this operation takesplace during one-half of a revolution of the pinon 29 or the entire time the set of teeth 27 on the mutilated gear 26 is in mesh therewith.

When the above operation is completed the mechanism will be in the position shown in Fig. 2. In this position the set of teeth on the mutilated gear 26 is just commend ing to mesh with the pinion 28 on the conveyor drive shaft 12a. Continued rotation of thegear 26 will rotate thev inion-23 and shaft 12a one-half of a revo ution, which, as described, is sufficient to cause the conveyor to advance the sheets of board' one step through the machine. When this operation is complete the second set of teeth` 27 on the mutilated gear 26 is'in position to again drive the pinion 29 for reciprocating table for a second operation. f

When the sheet of plaster board has been operated on by Aboth sets of cutters its face is formed with arcuate recesses of rectangular section arranged in rows, lthe recesses in each row being disposed at right .angles to and staggered with relation to the adjacent rows. This is clearly shown at B in Fig. 3 and Fig. 5.

lVhile we have shown the cut-ters in the arrangement'described, it is obvious that it is within the scope of the present invenl tion to arrange the cutters in any desired formation and also the shape and vdepth of the recesses may be such as deemed desir-- alble. i

Although we have shown the invention in the form now preferred by us, it is to be understood that various changes in the coinbination, construction and'arrangement `of parts may be made by those skilled in the art without departing from the spirit of the invention Ias claimed.

Having thus described our invention, what we claim and desire to secure by Letters Patent is:

l. A machine of the character described com risino' a frame a JluralitVT of circular boards being-.conveyed when positioned directly below said cutters, and other means adapted to slowly raise the boards into contact with the cutters, and then rapidly lower them during said interruption.

3. A machine of the character described comprising a frame, a plurality of rotatable cutters mounted on the frame, a conveyor mounted on the frame beneath the cutters, a vertically reciprocable table supported by the frame directly below the cutters, and means: for interrupting the movement of the conveyor at predetermined periods and vertically reciprocating said table during said interruptions.

sl. A machine of the character described comprising a frame, a plurality of rotatable cutters carried by the frame, guideways formed on the frame beneath the cutters, a vertically reciprocable table mounted between the guideways directly below the cutters, an intermittently operating conveyor adapted to convey boards along the guideways to said table, and means for reciprocating said table during the inoperative periods of the conveyor.

5. A machine of the character described comprising a frame, a plurality of hori- Zontally disposed mandrels journalled in the frame, circular cutters on said mandrels, a vertically reciprocable table mounted below said cutters, an intermittently operating feed means adapted to deliver boards singly to said table, and means for vertically reciprocating said table a distance less than the thickness of the board during the inoperative periods of said feed means.

6. A machine of the character described comprising a frame, two sets of cutters mounted on the frame and disposed at right angles to each other, an intermittently operating feed means adapted to convey boards to said sets of cutters successively, and means operative during the inoperative period of said feed means to vertically reciprocate boards positioned adjacent the cutters to force the surface of the boards into contact with the cutters.

7, A machine of the character described comprising a horizontal frame, two sets of rotary cutters disposed in the same plane above the frame and parallel thereto, each set comprising gangs of circular cutters arranged in spaced relation to each other upon parallel mandrels, the mandrels of the two sets o-f critters being disposed at right angles to each other, a table disposed beneath said cutters and over the face of which boa-rds may be moved, means for intermittently raising and lowering said table to place the uppermost faces of the boards raised thereon in cutting contact with the sets of cutters, and feed means intermittently operating while the table is in its lowermost position to move the board along the table to the cutting stations and whereby a board will first be moved in position to be acted upon by the first set of cutters in forming a plurality of parallel depressions in e ual spaced relation to each other over the ace of the board and will thereafter move to the second cutting station where the second set of cutters will act to form a plurality of equal spaced depressions in the face of the board and at right angles to the first formed depressions.

8. A machine of the character described comprising a frame, a horizontal table reciprocably mounted thereupon for vertical movement, said table being of a length and width capable of accommodating two lengths of board to be acted upon by the machine, a set of circular cutters disposed above the t-able and adapted to act upon the boards supported by the double section therebeneath, one set of cutters comprising a plurality of mandrils disposed in equal spaced relation to each other, and each carrying a plurality of circular cutters equal in number on the various mandrils, and the successive cutters on the various mandrils being in alignment whereby rows of spaced parallel depressions will be cut in the face of a board moved thereagainst, the second set of cutters being substantially the same as the first with the exception that their mandrils are disposed at right angles to the first set of cutters, means for intermittently advancing boards along the table to assume positions beneath the two sets of cutters whereby action by the firstL set of cutters will form depressions ext-ending in one direction over the face of the board and action by the second set of critters will form depressions at lright angles to said first formed depressions and between the rows thereof, and means for raising and lowering the table at intervals between the operation of the board feeding mechanism.

EDVARD WESTBERG. JOSEPH STRAND. 

